A Study to Assess the Efficacy and Safety of TC-5214 as an Adjunct Therapy in Patients With Major Depressive Disorder.

Exclusion Criteria

• •Patients with a lifetime history of bipolar disorder, psychotic disorder or post-traumatic stress disorder.
• •Patients with a history of suicide attempts in the past year and/or seen by the investigator as having a significant history of risk of suicide or homicide.
• •History of renal insufficiency or impairment or conditions that could affect absorption or metabolism of investigational product.